Its 43 mpg city figure for Toyota’s premier hybrid was also “a stunning 11 mpg improvement over the old version.” This sounds impressive, but the EPA does not rate the old version at a mere 32 mpg, but rather 51 mpg in the city, and this is a sizable discrepancy.

For its part, Consumer Reports says it has a more aggressive city cycle that more-closely represents real world driving than the federal government.

“Our city cycle consists of speed variations, some of which are 20 to 40 mph within a relatively short distance,” said Consumer Reports’ Gabriel Shenhar, program manager, Vehicle Dynamics, last month on a similar question regarding the Toyota RAV4 Hybrid. “We’ve modeled this course after a typical urban/suburban type driving pattern and we think it is representative of the city consumption most consumers experience. We’ve also validated it against survey results among our subscribers.”

CR’s highway result however turned out to be more easy going, as the feds only affix 50 mpg highway to the 2016 Prius, but CR says 59.

The usual advantage hybrids are known to offer – superior city mpg due to low-speed electric power sparing the engine, is thus turned on its head in Consumer Reports’ hands.

In fact, many people do drive differently, and while consumers would like an authority to tell them precisely how much mpg to expect, the real answer depends on them as individuals.

In regions with plenty of fast-paced, stressed-out drivers pushing to get where they are going, speed limits may routinely be exceeded, and aggressive fuel-sapping driving is common.

If you “go with the flow” in such situations, the truism “your mileage may vary” is all the more true. If you on the other hand can drive more sensibly, you can beat average numbers, and then you also have hypermilers who make a game of taking this to an extreme to radically beat averaged numbers.